Test gross business receipts to verify that all the gross receipts are accounted for. For additional techniques, see IRM（Internal Revenue Manual) 4.10.3.9, Testing Gross Receipts or Sales.

1. Trace original entries in the books back to the original sales document (e.g., sales slips, cash register receipts, or job contracts, etc.).
2. Trace original sales documents to the corresponding entries in the books.
3. If original sales documents are numbered or otherwise sequenced, identify and account for missing sales documents.
4. Determine the method and adequacy of the accounting for merchandise withdrawn for personal use.
5. Scan sales agreements, contracts and other related documents to identify unreported bonuses, awards, kickbacks, etc.
6. Determine that all accounts receivables are included in income for accrual basis taxpayers.

B、収入の証憑確認法Specific Item Method

1. The specific item method involves the use of direct evidence to determine the tax liability based on omitted income, overstated expenses, or both. For example, funds from known sources are tracked to deposits made to a taxpayer's bank account rather than analyzing bank deposits to identify unreported income from likely sources.
2. Direct evidence is evidence from which only one logical conclusion can be reached. Direct documentary evidence is generally regarded as having the greatest value; and, when possible, examiners should ask to see the original documents when there is reason to believe they exist. Documentary evidence should not be relied upon to the exclusion of facts established through oral testimony or other techniques, such as a tour of the business site.
3. The specific item method is appropriate when the taxpayer maintains books and records, adjustments are due to technical issues (such as timing or character of funds), or the potential sources of unreported income are limited (such as an insurance agent who underwrites for several companies).
4. The specific item method is not useful if the taxpayer's gross receipts are generated from numerous sources or in small amounts, such as a grocery store.

C、収入の間接的推定法Indirect Method

1. The indirect method involves the use of circumstantial evidence to determine the tax liability based on omitted income, overstated expenses, or both. Circumstantial evidence is evidence from which more than one logical conclusion can be reached. To support adjustments for additional taxable income, both the credibility of the evidence and the reasonableness of the conclusion must be evaluated before the determination of tax liability is made.
2. Analytical reviews and testing of the taxpayer's books and records, as required by the minimum income probes, may result in the identification of additional taxable income based on circumstantial evidence from which an inference can be made. The financial status analysis and bank account analysis are not prohibited by IRC 7602(e), Limitation on the Use of Financial Status Audit Techniques, simply because an adjustment to taxable income supported by indirect (circumstantial) evidence may be the result.
3. Evaluating Evidence, for complete discussion.

Formal Indirect Method

1. The formal indirect methods are audit techniques used to determine the tax liability based on the amount of unreported income.

2. The formal indirect methods are also known as financial status audit techniques. See IRM 4.10.4.6.1 for additional discussion. They are distinguishable from other audit techniques by the following characteristics:

1) Reliance on indirect evidence of income,
2) In-depth analysis of actual costs that requires the extensive collection of detailed information, and
3) Subject to IRC 7602(e), which states, "the Secretary shall not use financial status or economic reality examination techniques to determine the existence of unreported income of any taxpayer unless the Secretary has a reasonable indication that there is a likelihood of such unreported income."

3. Formal indirect methods are appropriate when:

1) The taxpayer's books and records are missing, incomplete, or irregularities are identified; or
2) The financial status analysis indicates a material imbalance of cash flows after consideration of other adjustments identified during the examination.